Press



Patented Nov. 20, 1951 PRESS Earl L. Schulman, Swissvale, Pa., assignorto Westinghouse Electric Corporation, East Pittsburgh, Pa., acorporation of Pennsylvania Application December 30, 1947, Serial No.794,613

3 Claims.

This invention relates generally to presses and more particularly to apress for consolidating materials.

An object of this invention is to provide, in a press having a pressurechamber, for sealing the pressure chamber of the press during a pressingoperation.

A further object of the invention is to provide, in a press having apressure chamber formed by an elastic diaphragm and a press head, forsealing the elastic diaphragm to the press head during a pressingoperation.

Other objects of the invention will in part be obvious and will in partappear hereinafter. For a better understanding of the nature and objectsof the invention, reference should be had to the following detaileddescription taken in conjunction With the accompanying drawing, inwhich:

Figure 1 is a view in cross section of an apparatus embodying thefeatures of the invention; and

Fig. 2 is a View in cross section of another embodiment of thisinvention.

Referring to Fig. 1, there is illustrated a press I comprising a pair ofplatens I2 and I4 which are provided with means (not shown) for movingthem relative to each other into cooperating pressing relationship.

The platen I2 is provided with a depending rim member it. Asillustrated, an impervious flexible diaphragm 20 is disposed across andin spaced relation to, the face II of the platen I2 and in seatingengagement with the rim member I8 to form a pressure chamber or spaceIG. In the embodiment illustrated, the flexible diaphragm 2B is securedto the sides of the platen I2 by fastening means 22 which in thisinstance comprises a metal band. In practice, the flexible diaphragm 2Gis preferably an elastomer such as rubber or a silicon polymer capableof withstanding elevated temperatures.

A conduit or aperture 24 is disposed in the platen I2 for introducingsteam or hot water or other suitable fluid under pressure into the spaceI6. Cooling water may be introduced in the space II; by the conduit 26and vented through the conduit 28.

The platen I l includes a continuous channel 30 disposed in the pressingface 3| adjacent to the outer edge thereof and conforms to theconfiguration of the depending rim member I8 disposed in the face ofplaten I2.

Although the rim member I8 has been described hereinbefore as beingadjacent to the outer edge of platen I2, it will be understood that theprojecting member I8 may be disposed in a predetermined path on the faceof platen I2 .to form a cavity it of any required configuration in whichcase the channel 3!) is disposed in platen I4 in a configurationconforming to the path of the member I8.

A flexiblev tubular member 32 is disposed in the channel 30 andconnected by conduit 33 extending through the platen I4 to a source offluid supply (not shown) for supplying fluid under pressure to themember 32. A heating means is provided in the platen I4 such as coils ortubes 34 through which a heating fluid may be circulated to securepredetermined temperatures.

The operation of the apparatus will be described in connection with aspecific application, which is the production of bonded mica sheets bythe method disclosed in my copending application Serial No. 696.601,filed September 12, 1946, now Patent No. 2,524,932, but it will beunderstood that the description of this specific application is given inan illustrative and not in a limiting sense.

In operation, a layer 36 of mica flakes and an uncured flowable binderdistributed through the mica flakes is placed on the platen I4. Theplatens I2 and I4 are then actuated into coopcrating pressingrelationship whereby the flexible diaphragm 20 contacts the layer 36 ofmica and binder and the platen I4 contacts the por-' tion of theflexible diaphragm 20 disposed over the depending member I8 along acontinuous predetermined path.

The channel 30 is disposed as hereinbefore described in the platen l4 insuch relation to the depending member I8 that when the platens I2 and I4are in pressing relationship, the portion of the flexible diaphragm 20disposed over the depending member I8 covers the continuous channel 30throughout its length.

While the platens I2 and I4 are being held in pressing relationship, afluid is admitted under pressure to the interior of the tubular member32 to expand it to exert force against the adjacent portion of theflexible diaphragm 26 thereby forcing the diaphragm 20 into sealingengagement with the depending member I8.

Steam or hot water is then admitted under pressure through the conduit24 into the space It, thereby forcing the flexible diaphragm 23 againstthe surface of the mica layer 36. It will be understood that thepressure applied to the tubular member 32 should be substantiallygreater than the pressure in the space I6 to effect a satisfactorysealing engagement between the flexible member I6 and the dependingmember l8. Inasmuch as the tubular member 32 forces the flexiblediaphragm 20 into sealing contact with the depending member I8 on acontinuous path of a predetermined configuration, the fluid applied tocavity I6 is thereby prevented from escaping from between the flexiblemember 26 and the depending member I8. Heat from the steam or hot waterin the space It is transferred through the flexible diaphragm 29 to thelayer 36 of mica and binder and simultaneously steam or hot water may beadmitted to the tubes 34 in the platen 14 for heating the layer ofmicaand binder from the underside.

In the specific application of the apparatus to the manufacture ofbonded mica sheets, it is preferred to admit steam at a pressure ofbetween about 20 and 100 pounds per square inch to the space 16 toaccomplish the consolidation of the mica and binder. The pressureapplied to the flexible tube 32 should in every case be greater than thepressure in the space IE, to effect satisfactory sealing between theflexible diaphragm 26 and the depending or projecting member is ashereinbefore described.

At the end of the predetermined pressing period, the pressure in cavityI6 is released and cooling water may be admitted through conduit 26 andvented through conduit 28, thereby cool- .4 tinuous projecting portiondisposed on the face of one of the platens in a predetermined manner toform an enclosed area thereon, an impervious -elastie diaphragm disposedin seating relationship on the continuous projecting portion across theenclosed area to form a space between the elastic diaphragm and the oneplaten, means for ing the mica sheet 36. When the sheet has cooledsufliciently, the cooling water is shut off, the

pressure applied to the tubular member 32 is re- 1 leased and the presshead separated for removal of the consolidated mica sheet 36.

Fig. 2 illustrates another embodiment of this of the platen face I I' bya clamping ring 38. The

clamping ring 38 is held in position with respect to the platen l2 bymeans of screws 39 disposed in spaced relation along the ring 38. Aconduit 24 is disposed in the platen l2 for the admission of fluid totransmit pressure to the flexible member and the platen 12.

In the embodiment of Fig. 2, projecting members 40 and 42 are disposedin spaced relation to each other on and carried by the face 3| of theplaten M in a predetermined path to form a cavity 44 of predeterminedconfiguration within the confines of the projecting member 42; Theprojecting member 40 is positioned on the face 3| of platen 14 in suchrelation to the position of clamping ring 38 disposed on platen l2 as topermit engagement of the projecting members lie and 42 with the flexiblediaphragm 20 when the platens are in pressing relationship. Theprojecting members 60 and 42 are disposed in spaced relation to oneanother for cooperating to form a continuous channel 26 therebetween forreceiving the flexible tubular member 32.

In operation a layer 36 of mica flakes and uncured flowable binder isplaced in the cavity 64, and the platens l2 and 14 are then actuatedinto cooperating pressing relationship, whereby the projecting membersand 42 contact the flexible diaphragm 20. The pressure thereafterapplied to the interior of the tubular member 32 causes expansion of thetubular member against the flexible diaphragm 20', forcing the flexiblediaphragm into sealing relationship with the platen face ll along acontinuous line contact of predetermined configuration, to prevent lossof pressure from between the flexible member 20' and the platen face Ii.

It will be understood that changes may be made in the structure of theapparatu disclosed without departing from the spirit of the invention.

I claim as my invention:

1. A press comprising, a pair of relatively movable aligned platenshaving opposed faces, a conapplying fluid pressure to the space, acontinuous channel disposed in the face of the other platen in alignmentwith the continuous projecting portion of said one platen, a flexibletube disposed in the channel, means for appliyng pressure to theinterior of the flexible tube when the platen faces are in pressingrelationship whereby the flexible tube contacts the elastic diaphragm toforce the diaphragm into sealing contact with the projecting portion ofthe one platen to prevent loss of fluid pressure fromsaid space.

2. A press comprising, a pair of relatively movable platen havingopposed faces disposed for movement into cooperating pressingrelationship, a projecting portion disposed on the face of one of theplatens adjacent to the outer. edge and substantially conforming to theconfluration thereof, an impervious elastic diaphragm disposed over theface of the oneplaten in seating relationship on the projecting portionto form aspace between the elastic diaphragm and the one platen,

mean for applying fluid pressure to the space, a

continuous channel formed in the other platen adjacent to the outer edgethereof and conforming to the configuration of the projecting portion onsaid one platen, a flexible tube disposed in the channel, means forapplying pressure to the interior of the flexible tube when the platenfaces are in pressing relationship whereby the flexible tube contactsthe elastic diaphragm and forces it into sealing contact with theprojecting portion of said one platen to prevent loss of fluid pressurefrom said space.

3. In a press, the combination comprising, a pair of relatively movableplatens having opposed faces disposed for movement into cooperatingpressing relationship, a continuous projecting portion carried by one ofthe platens to form a cavity of predetermined configuration on the facethereof, an impervious elastic diaphragm disposed across the face of theone platen in seating engagement with the projecting portion to form aspace between the elastic diaphragm and the one platen, means forapplying fluid pressure to the space, a continuous channel disposed inthe face of the other platen to conform to the configuration of thecontinuous projecting portion, a flexible tube disposed in the channel,means for applying pressure to the interior of the flexible tube greaterthan the pressure applied to said space whereby the flexible tubecontacts the elastic diaphragm when the platen faces are in pressingrelationship to force the elastic diaphragm into sealing contact withthe projecting portion of the one platen to prevent loss of fluidpressure from said space.

EARL L. SCHULMAN.

REFERENCES CITED The following references are of record in the flle ofthis patent:

UNITED STATES PATENTS Number Name Date 1,146,413 Edison July 13, 19151,260,002 Lanhoffer Mar. 19, 1918 1,806,861 Owen May 26, 1931 2,288,356Humphrey June 30, 1942

